Process for recovering metal.



A. W.-DIAOK." PROGESSIOR REGOVERING METAL.

APIELIOATION FILED JUNE 8, 1010.

awuv/wto c 1 A K Qwokxkcdek Love k.

ARCHIIBALD W. DIAGK, OF DETROIT, MICHIGAN.

Specification of Letters Patent.

PROCESS FOR RECOVERING METAL.

Patented Sept. 6, 1910.

Application filed June a, 1910. Serial No. 565,802.

"To all whom it may concern:

Be it known that I, AROHIBAL W. DIACK, a citizen of the United States,and a resident of Detroit, in the county of Wayne and State of Michigan,have invented a new and useful Process for Recovering Metal, of whichthe following is a specification.

This invention comprises a process for recovering metals from skimmings,and other dross, and for melting down borings and other small particlesand pieces of such metals as readily oxidize when heated.

WVhile this process is not necessarily carried out by any particulartype of mechanism, and any other construction may be employed, thatshown in the drawing embodies features necessary to the carrying outofthis process. An oil, gas, orsolid fuel furnace 1 of well knownconstruction, contains the crucible 2 and is closed by the cover 3having an opening closed by the lid 4. A top 5 partly covers thecrucible and has an opening 6 through which access is had to thecontents. A refractory tube 7, unacted upon at the temperature employed,preferably of carbon, extends down into the crucible below the line ofthe molten contents.

Above the furnace may be mounted a hopper 10 having a spout l1connecting with the pipe 12, which pipe connects to the tube 7 in anydesirable manner, a connecting sleeve 13 being shown. At the upper endof the pipe 12 may be mounted a frame 9,

tube 15.

in which are revoluble the shaft 14 and a On the shaft 14 may be secureda pulley 16 and a pinion 17, which latter meshes with the gear 18 on thetube 15. A screw-conveyer 19 is secured to the tube 15 and will beturned by the shaft 14. The parts above the furnace top 3 may all be ofcast iron, and any other mechanism may be employed to force the materialdown the tube 7. Arrangements may also be made for preheating thematerial in its pasage from the hopper to the molten metal inthecrucible.

Dross such as skimmings from melted aluminum and of light-welght alloyscontain large amounts of metal. When such dross is packed into acrucible and heated to the melting point of the metal or alloy, theoxids and other impurities do not sepa rate readily, as their specificgravity is so nearly that of the metal or. alloy. In view to the pipe 12through the spout 11. The

screw 19 slowly feeds down this material at a constant speed, forcing itdown into the molten mass which fills the lower end of the tube 7. Bythe time the material is forced out of the lower end of the tube, themetal will have been melted and absorbedby the molten mass in thecrucible and the oxid will float to the surface 21 of the mass. As moremetal is added to the amount already in the crucible, and the surfacerises, the oxid will come near to the opening 6 where it can be skimmedoff.

In order to insure easy movement the tube 7 may be formed slightlytapering, the smaller end being upward. A metal rod can be thrust downthrough the bore 20 of the tube 15, should the material bridge or cakein the tube7.

This process may be modified to recover the metal of borings and scrapsof such metals as readily oxidize near the melting point. A quantity ofthe metal is first melted, after which the borings and scraps are forceddown into the molten mass through the tube 7. This tube prevents theoxldizing flame from reaching the finely divided metal, which reallydoes not melt until under the surface of the main mass. The tube 7 orits equivalent can be filled with an unoxidizing or neutral atmosphereso as to further protect the metal.

It is sometimes desirable to mix a proper flux such as ammonium chloridwith the mixed metal and oxids and with the metal boringsbeforesubmerging the' same in the molten metal.

Having now explained my process, what I claim as my invention and desireto secure by Letters Patent is 1. The process of recovering lightmetals,

which consists in mechanically feeding par- 'of a higher ticles of thesame down through a. convey: ing tube whose lower end is submerged in amass of molten metal. I

2. The process of recovering metals from a mixture of metals and oxidsof the same, which consists in mechanically feeding the mixture downthrough a tube whose lower end is submerged in a mass of molten metalsspecific gravity than the metals recovered.

3. The process of separating metals from'a mixture of the same andimpurities, which,

consists in mechanically feeding the mix- "ture down a tube having itslower end submerged in molten metals and permitting the impurities torise to the surface.

4. The process of recovering metals,

which consist in mechanically feeding particles of the same down into amass of molten metals While protectin the same from oxidation by theflame which keeps up the tem- V perature of the mass of the moltenmetals.

5. The process of. recovering easily-oxidized metal from impuritieswhich consists in feeding particles of the same into a mass of moltenmetal through a conveyer which is filled with a non-oxidizing gas.

In testimony whereof I have signed this

